It is generally accepted that the natural flavor of maple sugar and maple syrup and the synthetic flavor produced by 2-hydroxy-3-methylcyclopent-2-ene-1-one are the same and that the responsible compounds are the same compounds. The synthetic flavor compound is often called maple lactone because of its flavor and because of its existence in maple sugar and other maple products even though it is not truly a lactone, that name having been given before its chemical structure was known.
Maple lactone finds immediate and practical utility as a flavoring agent in the preparation of maple syrup and other artificially flavored maple products
Because some the sources of natural maple flavoring substance have declined and because the number of people who consume maple products has increased, there is a need for efficient and economical methods for producing maple lactone.
The Dieckmann reaction for producing maple lactone is disclosed in U.S. Patent No. 3,922,296 issued to McFearin (hereinafter McFearin '296). The McFearin process requires a step of adding methyl bromide, which adds to the cost and complexity of the process, and adds to the waste disposal expense. Several of the U.S. Patents which the inventors hoped would be useful toward the end of preparing maple lactone or related compounds are discussed in McFearin '296.